Safety switch



Dec. 2, 1941. J. w. SAMZELIUS SAFETY SWITCH Filed April 27, 1940WITNESSES:

John W. ScwzzeZz'z/s.

Patented Dec. 2, 1941 UNiTED SAFETY SWITCH Pennsylvania ApplicationApril 27, 1940, SerialNo. 332,045

Claims.

In safety switches of some types, the switch blades are actuated by aone-piece crank and operating handle, the crank portion being disposedinside of the cabinet and the handle portion on the outside. In thepast, the usual practice has been to insert the crank by snaking thebends through a hole in the side of the cabinet. Such a method is notentirely satisfactory because of the time required to make the assemblyand also because of the fact that the hole in the handle side of the boxmust be larger than is desirable to make a good bearing for the crank.

An object of my invention, generally stated, is to provide a safetyswitch which shall be simple and efficient in operation and which may beeconomically manufactured and installed.

A more specific object of my invention is to simplify the assembling ofa one-piece crank and operating handle in a safety switch cabinet.

Another object of my invention is to provide a combined mounting for thecrank and latch for the cover of a safety switch cabinet.

A further object of my invention is to provide a relatively tightcabinet for an electric switch.

Still another object of my invention is to provide a combined bearingplate and stop member for the crank and handle of a safety switch.

Other objects of my invention will be explained fully hereinafter orwill be apparent to those skilled in the art.

In accordance with my invention, a relatively deep slot, into which thecrank is dropped, is provided in the handle side of a safety switchcabinet. The side wall is slit at right angles to the slot at two placeson each side of the slot and the portions between these slits are bentinwardly in a short S-bend to form guides for a spring steel striphaving a slot for the crank near one end and a catch for the lid nearthe other end, which is hooked over the crank and pushed downwardly inthe guides as the crank goes down into the slot in the side wall of thecabinet.

For a fuller understanding of the nature and objects of my invention,reference may be had to the following detailed description, taken inconjunction with the accompanying drawing, in which:

Fig. 1 is a view, in side elevation, of a safety switch cabinetembodying my invention, a portion of the cover being broken away forclearness;

Fig. 2 is a sectional view, taken along the line II--II of Fig. 1;

Fig. 3 is a view, in side elevation, of a portion of a side wall of thecabinet shown in Fig. 1;

Fig. 4 is a view, in elevation, of a combined latch and crank mountingutilized in the structure shown in Fig. 1; and

Fig. 5 is a View, in perspective, of a combined stop and bearing platealso utilized in the cabinet structure.

Referring to the drawing, and particularly to Fig. 1, the structureshown therein comprises a cabinet It for enclosing a switch mechanism(not shown). Thecabinet It is provided with a cover II which may behinged to the cabinet at one side in the usual manner.

In accordance with the usual practice, a onepiece operating crank 12having a handle .portion I3 disposed exteriorly of the cabinet isprovided for actuating the switch mechanism. As explained hereinbefore,the usual practice has been to mount the operating crank I 2 in holesprovided in opposite side walls of the cabinet Iii, the side wallsthereby supporting the operating crank and serving as bearings for thecrank member. However, as explained hereinbefore, considerabledifiiculty is usually experienced in assembling the crank member in thecabinet unless one of the holes is made considerably larger in diameterthan the crank, in which case it does not provide a suitable bearing forthe crank.

In order to overcome the foregoing difiiculty, I have provided a slot I4in one side wall of the cabinet H3. The slot I4 is approximately thesame width as the diameter of the crank and a bearing aperture I5 isprovided at the bottom of the slot.

As shown in Fig. 3, two slits 5 are made in the side wall on each sideof the slot M at right angles to the slot and, as shown in Fig. 2, thematerial between each pair of slits is bent inwardly in a short S-bendto form guide mem! bers H.

A latching strip 18, which is preferably comprised of spring steel andis of suificient width to cover the slot i4, is disposed between theguide members I! and the inside of the side wall of the cabinet 1'0. Asshown in Fig. 4, the strip 18 is preferably provided with a slot [9 inone side near the lower end of the strip. The slot I9 is approximatelythe same width as the diameter of the crank l2 and a bearing aperture 2!is provided at the bottom of the slot l9. If desired,

the slot I9 may be vertically disposed in the bottom end of the strip18, or a hole hold of sufficient diameter to permit the strip to bethreaded over the crank, may be utilized. However, the structure shownin the drawing is preferable for assembly purposes, as will be explainedmore fully hereinafter.

The strip I 8 is of sufficient length to extend through a suitable slot22 in the cover H and is provided with a barb 23 for engaging the coverto retain it in the closed position on the cabinet. Since the strip ispreferably comprised of spring steel, the catch 23 may be easilyreleased from the cover by pressing on the upper end of the strip.

In order to assemble the crank [2 in the cabinet, it is merely necessaryto hook the slot l9 over the crank I2 and start the strip 18 between theguide members I! and the inside of the cabinet wall. The strip may thenbe forced downwardly between the guides by pressing down on the handleportion 13 of the crank [2. It will be seen that the strip I8 not onlycloses the slot M to form a relatively tight cabinet, but also providesa bearing surface for the crank I2 since the apertures l5 and 2| areconcentrically disposed when the crank is in its operating position.Furthermore, the strip l8 functions as a latch for retaining the coverin the closed position and since the strip is made separately from theremainder of the cabinet, it may be composed of a high grade of springsteel, thereby providing an efficient latch member.

In order to fasten the strip I8 and the operating crank in position, apair of holes 24 are provided in the strip 18 and material may be forcedfrom the side wall of the cabinet into these holes by means of a centerpunch or other suitable tool. If desired, the strip may be secured inposition by spot welding or methods.

If it is desired to provide additional bearing surface for the crank l2,a bearing plate 25 may be secured to the outside of the side wall of thecabinet. As shown in Fig. 5, the bearing plate 25 is provided with abearing aperture 26 which is concentric with the apertures l5 and 2!when the plate is secured to the cabinet as shown in Fig. l. The plate25 may be secured to the cabinet by spot welding or by screws or rivetsinserted in holes 21 provided in the bearing plate.

In order that the handle portion l3 of the operating crank shall bestopped at predetermined position, namely, the off and on positions ofthe switch mechanism, ears 28 are provided on the bearing plate. Asshown, the ears 28 are perpendicular to the surface of the cabinet sidewall and are so disposed that they stop the movement of the handle atthe desired positions. A hole 29 is provided in each one of the ears 28to permit a padlock or other suitable locking device to be utilized forlocking the handle [3 in either the oif or the on position. A hole 3|may be provided near the top of the latching strip I8 to perotherwell-known mit the cover II to be locked in the closed position, ifdesired.

From the foregoing description, it is apparent that I have provided asafety switch cabinet which may be manufactured economically and whichgreatly facilitates the assembly of the switch structure and itsoperating mechanism. Furthermore, the cabinet is relatively tight inconstruction, thereby excluding dirt and moisture from the cabinet aswell as reducing the fire hazard caused by arcs drawn on the inside ofthe cabinet.

Since numerous changes may be made in the above described constructionand different embodiments of the invention may be made without departingfrom the spirit and scope thereof, it is intended that all mattercontained in the foregoing description or shown in the accompanyingdrawing, shall be interpreted as illustrative and not in a limitingsense.

I claim as my invention:

1. In an enclosed switch structure, in combination, a switch cabinethaving a slot in one side wall thereof, a switch actuating memberdisposed in the slot, guide members formed integrally with said sidewall, and means disposed in said guide members for covering said slotand retaining said actuating member at the bottom of said slot.

2. In an enclosed switch structure, in combina tion, a switch cabinethaving a slot in one side wall thereof, a switch actuating memberdisposed in the slot, a guide member formed integrally with said sidewall at each side of said slot, and means disposed between said guidemembers for covering said slot and retaining said actuating member atthe bottom of said slot.

3. The combination with a switch cabinet having an openable cover and anactuating crank, of a spring strip having a bearing aperture therein forthe crank and a catch thereon for releasably latching the cover on thecabinet, and guide means for said strip formed integrally with thecabinet.

4:. The combination with a switch cabinet having an openable cover andan actuating crank, of a spring strip having a bearing aperture thereinfor the crank and a catch thereon for releasably latching the cover onthe cabinet, guide means for said strip formed integrally with thecabinet, and means for securing said strip to the cabinet therebyretaining the crank in it operating position.

5. In a switch cabinet having an openable cover and a slot in one sidewall, in combination, a one-piece operating crank disposed in said slot,a resilient strip having a bearing aperture therein for the crank and acatch thereon for releasably latching the cover on the cabinet, saidstrip being disposed to substantially close said slot, and a bearingplate secured to the cabinet and having stops thereon for engaging saidcrank in predetermined positions.

JOHN \V. 'SAMZELIUS.

